Bill Gates thinks big. His charitable foundation has poured $1 billion into the fight against that great scourge of humankind, malaria, resulting in the creation of a new vaccine that is 100% effective in mice, and is now headed towards trials in humans. If successful, Gates' efforts have the potential to save millions of lives. Gates has also turned his attention to another great scourge of humankind, the hurricane. In a 2008 patent filing that recently came to light, Bill Gates and his friends presented a scheme for reducing the strength of hurricanes by cooling sea surface temperatures, using a fleet of ships that bring up cold water from the depths. Can Gates really pull this off? I don't think so. The obstacles are fourfold: technical, financial, environmental, and legal.

Figure 1. A diagram from a 2008 Bill Gates patent filing, depicting an array of hurricane-control vessels in the Gulf of Mexico. Image credit: techflash.com.

Technical issuesWhile modification of hurricanes is theoretically possible, the scale of the undertaking is truly enormous. A fleet of dozens or hundreds of ships spanning a huge swath of ocean would be required, and these ships would have to be able to withstand the 50-foot waves and 160 mph winds a major Category 5 hurricane could deliver. As I discussed when a similar scheme was proposed in 2006 by Atmocean, Inc., it is not clear how long the cold water pumped to the surface will stay there--the cold water pumped to the surface is more dense than the water beneath it, and so will tend to sink, allowing warmer water beneath to replace it and warm the surface waters again. Modeling studies and field studies are needed to determine if the cold water can stay at the surface long enough to significantly affect a hurricane. Furthermore, simply cooling the ocean may have no effect on a hurricane, if the storm is in a favorable upper-atmospheric environment with low wind shear.

Financial issuesAny hurricane modification effort is going to be tremendously expensive. The cost of the array of cooling pumps proposed by Atmocean in 2006 for the Gulf of Mexico was pegged at $2.4 billion. Gates' scheme would have a similar cost. He proposes paying for it through government funding and the sale of insurance policies in hurricane-prone areas.

Environmental issuesA large change to the ocean temperatures over a wide area of ocean is bound to have significant--and unknown--impacts on fisheries and wildlife. Regional weather patterns may also be affected, intensifying droughts or bringing heavy rains and flooding.

Legal issuesHurricanes naturally make sudden unpredictable course shifts, and the hurricane modification efforts are also capable of causing track shifts in a storm. Residents on the coast hit by the modified storm will want to sue, and there will be many lawyers more than happy to take their case. Gates would have to get special legislation passed to protect his company from lawsuits, such Congress passed for the gun industry in 2006.

SummaryIn summary, we simply don't know enough about hurricanes yet to safely engage in modifying them. A lot more research is needed before we should spend the huge sums needed to attempt hurricane modification. The Department of Homeland Security has a $1 million research effort going that will attempt to answer some of these questions, called HURRMIT (The Identification and Testing of Hurricane Mitigation Hypotheses). The HURRMIT program is evaluating the potential of a number of hurricane modification techniques, including:

Pumping cool water from the depths to the ocean surface in front of the hurricane (Ginis and Kithil, 2008)

Frankly, I'm dubious that the money being spent on HURRMIT is worth it, given the four huge obstacles to hurricane modification I presented above. However, the research may provide some new insights into hurricane intensification that we don't have now.

In closing, I'll present the proposal one reader of an New Orleans online newspaper had:

"[Bill Gates] should just have one of his employees write an ActiveX Script for Google maps so we can just highlight the hurricane, right click on it, then select delete. Or maybe just cut and paste it farther out into the Atlantic Ocean."

Controlling hurricanes, Hollywood styleHollywood's latest attempt to create a weather disaster epic is itself a disaster, as many of you who suffered through last night's installment of "The Storm" miniseries on NBC will agree. The uninspired plot involves government/military bad guys and a noble scientist who heroically tries to save the world, with a good measure of made-for-TV chase scenes, murders, and special effects thrown in. The hero scientist Dr. Jonathan Kirk (James Van Der Beek) has a scheme whereby one can control the weather by bouncing crackling streams of energy from a ground-based array of dishes off of satellites and into the ionosphere, which then gets "peeled away like an onion". Dr. Kirk then uses the energy to bring life-giving rains to the Sudan, and to steer a hurricane away from Florida. The trouble is, he doesn't quite have things figured out. Unintended side effects occur, such as the Mojave Desert getting 8 inches of snow the day after 112°F temperatures. More problematically, the hurricane heading for Florida strengthens instead of weakening. In one scene, a radar animation of the hurricane off the coast of Florida shows the powerful storm spinning clockwise instead of counter-clockwise, defying the laws of physics. Hmm, that's some pretty powerful weather control technology! The scientific basis for the weather control scheme is preposterous--ground-based energy streams beamed into the ionosphere would not appreciably affect the weather. The weather is made in the troposphere, the layer of atmosphere closest to the ground. Furthermore, the amount of energy needed to cause the kind of disturbances portrayed in the movie are enormous, similar in scale to the entire electrical output of the world. A small array of ground-based dishes could only channel perhaps a trillionth of the amount of energy required. The movie's special effects are cheesy, the acting average, the plot weak, and the science behind the the story completely implausible, making this weather disaster movie as disastrous as the equally rotten Day After Tomorrow movie. The movie's main redeeming grace is as a cautionary tale--weather modification on a large scale will certainly have unintended side effects, and we should not engage in such efforts until we have a much greater understanding of how the weather and climate work.